Liquid film thickness in a rotating disc gas-liquid contactor

doi:10.1016/0043-1354(78)90136-7

Water Research

Volume 12, Issue 8, 1978, Pages 577-581

https://doi.org/10.1016/0043-1354(78)90136-7 Get rights and content

Abstract

For a rotating disc gas-liquid contactor a relationship has been derived between the amount of liquid entrained by a disc and its rotational velocity: $δ = KV 12$ where δ is a mean film thickness on the disc, K is a function of the acceleration of gravity and the kinematic viscosity and V_c is the vertical component of the circumferential velocity where the disc emerges from the liquid. For water at 20°C the experimental value for K was estimated: 1.31 10⁻⁴ $m 12$ $s 12$ , which compares well with the theoretical value of 1.20 10⁻² $m 12$ $s 12$ .

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These results indicated that wind speed influenced the oxygen concentration in the biofilm, and this influence presented the same trend as the concentration change and decreased with the biofilm depth. Furthermore, as reported, the thickness of liquid film is affected by the rotational velocity of the disc (Zhevalkink et al., 1978). Therefore, during the exposure stage, the relative movement between the biofilm and the air will affect the liquid film thickness, which will then affect the mass transfer resistance and mass transfer coefficient of the liquid film.
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Liquid film thickness in a rotating disc gas-liquid contactor

Abstract

Water Res.

Water Res.

Chem. Engng Sci.